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<h2><a name="SECTION0014320000000000000000">
12.3.2 Sequential (de)compression</a>
</h2>

<p>
Sequential compression and decompression is done using the classes
<tt class="class">BZ2Compressor</tt> and <tt class="class">BZ2Decompressor</tt>.

<p>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><span class="typelabel">class</span>&nbsp;<tt id='l2h-2348' xml:id='l2h-2348' class="class">BZ2Compressor</tt></b>(</nobr></td>
  <td><var></var><big>[</big><var>compresslevel</var><big>]</big><var></var>)</td></tr></table></dt>
<dd>
Create a new compressor object. This object may be used to compress
data sequentially. If you want to compress data in one shot, use the
<tt class="function">compress()</tt> function instead. The <var>compresslevel</var> parameter,
if given, must be a number between <code>1</code> and <code>9</code>; the default
is <code>9</code>.
</dl>

<p>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><tt id='l2h-2349' xml:id='l2h-2349' class="method">compress</tt></b>(</nobr></td>
  <td><var>data</var>)</td></tr></table></dt>
<dd>
Provide more data to the compressor object. It will return chunks of compressed
data whenever possible. When you've finished providing data to compress, call
the <tt class="method">flush()</tt> method to finish the compression process, and return what
is left in internal buffers.
</dl>

<p>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><tt id='l2h-2350' xml:id='l2h-2350' class="method">flush</tt></b>(</nobr></td>
  <td><var></var>)</td></tr></table></dt>
<dd>
Finish the compression process and return what is left in internal buffers. You
must not use the compressor object after calling this method.
</dl>

<p>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><span class="typelabel">class</span>&nbsp;<tt id='l2h-2351' xml:id='l2h-2351' class="class">BZ2Decompressor</tt></b>(</nobr></td>
  <td><var></var>)</td></tr></table></dt>
<dd>
Create a new decompressor object. This object may be used to decompress
data sequentially. If you want to decompress data in one shot, use the
<tt class="function">decompress()</tt> function instead.
</dl>

<p>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><tt id='l2h-2352' xml:id='l2h-2352' class="method">decompress</tt></b>(</nobr></td>
  <td><var>data</var>)</td></tr></table></dt>
<dd>
Provide more data to the decompressor object. It will return chunks of
decompressed data whenever possible. If you try to decompress data after the
end of stream is found, <tt class="exception">EOFError</tt> will be raised. If any data was
found after the end of stream, it'll be ignored and saved in
<tt class="member">unused_data</tt> attribute.
</dl>

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<span class="release-info">Release 2.5.1, documentation updated on 18th April, 2007.</span>
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